The biggest obstacle here is what his dad is going to allow. If his dad won't buy ham for a chez sandwich, what will he buy? My head explodes with ideas I'd love to share with him, but I'm reluctant because of his dad. Maybe I'm just "over thinking the plumbing".
His dad already buys eggs and cheese. Bacon can be inexspensive if you look for it. Potatoes are cheap as well. Alot can be done with those items less exspensive than Hot Pockets or frozen pizza.
Baked potato with butter, bacon and chez. Potatoes au gratin, mashed potatoes, potatoe cakes, omelettes, breakfast for dinner.....
One of my favorites, even if I'm not on a budget. Mahatma yellow rice, onion and broccoli. I like to add chicken and jalapeno, but it's good without. With all ingredients, it will feed 4 at 1.33 per portion. Regular white rice is cheaper and will work also. Add some of that chez if you want. Spread it on your bread as a sammich, I have.
I can think of things to do with what he already has and a box of bisquick.